<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <script type="text/javascript" >
    	 let user1 ={
    	     id:10,
             age:20,
             name:"dsadasd"
         }
         let user2={
    	     id:15,
             age:20
         }
         let user3={
    	     age:666,
    	     sex:1,
             address:"haha"
         }
         user3.mimimi='8888';
         Object.assign(user1,user2,user3)
        console.log(user1);
        console.log(user2);
        console.log(user3);
    </script>
</body>
</html>